Voice transmitters for telephone communication have long been known. In spite of the great advances in telephone communication over the years, the problem of transmitting a speaker's voice clearly in a high ambient noise environment has remained largely unsolved.
When using telephones equipped with prior art transmitters in high background noise environments, the speaker must often raise his voice to be heard over the background noise. This may cause the transmitter circuitry to saturate, resulting in distortion of the speaker's voice. High background noise also produces excessive side tone at the speaker's receiver. Side tone is commonly understood to mean the portion of the speaker's signal which appears at his own receiver without appreciable delay. Side tone causes the speaker to lower his voice, reducing the voice volume which the listener receives. A certain amount of voice side tone is desirable to prevent the phone from sounding "dead" to the speaker. In high ambient noise enviroments, excessive amounts of noise side tone may be generated so that the speaker is unable to hear his own voice at the receiver. Telephones provided with receiver amplifiers further aggravate this problem by providing amplification of the noise side tone.
The instant invention avoids the drawbacks of prior art transmitted by transmitting pure, clear sound and by eliminating excessive noise side tone.
The speaker's voice can be heard clearly over background noise without the need for shouting and without distortion.
The invention permits clear transmission of the speaker's voice even when it is necessary to speak softly.
Further, the invention is ideally suited for use with acoustic couplers of computer data communications.